Heat the oven to Gas Mark 4, 180°C (350°F). Place the garlic, ginger, soy sauce, sesame oil, one tablespoon oil, vinegar, five spice powder and brown sugar in a large bowl and mix to combine. Add the beef, toss to coat and set aside in the fridge for 1 hour to marinate, if possible. To cook the steaks: When you are ready to cook the steaks remove them from the marinade and pat dry. Reserve the marinade to use later. Season the steaks with salt and black pepper. Heat a little oil in a frying pan until really hot. Cook the steaks in batches. Allow two minutes on each side. Depending on how thick the steaks are and how you like them cooked, you may need to cook them for a further one or two minutes on each side. Let the steaks rest while you make the salad. To make the salad: Heat a little more oil in the same frying pan over a high heat. Add the mushrooms and chilli and cook for 5 minutes. Place in a large bowl. Add the reserved marinade to the frying pan. Rinse out the bowl the marinade was in with a couple of tablespoons of water and add this to the frying pan. Bring to a simmer and cook for 2 minutes or until slightly reduced. Then add it into the bowl with the mushrooms. Add the cooked noodles, lime zest, juice and cucumber to the bowl and gently toss to combine. Keep aside a tablespoon of the coriander leaves and half the scallions. Stir the rest through the noodles. Taste and season. Sprinkle the reserved coriander leaves and scallions over the top.
Slice the steaks and serve them along with the noodle salad.